This invention relates to a cutter for optical fibers made of a plastics.
One example of such a cutter for optical fibers is shown in FIGS. 1a-1c. The cutter includes an upper frame 12 and a lower frame 24 whose ends are pivotally connected by a pin 14 as shown in FIGS. 1a and 1c (the upper and lower relation therebetween is referred to the drawings). The upper and lower frames 12 and 24 are provided with abutting surfaces 13 and 25 adapted to abut against each other when pivotally moved toward each other.
A spring 16 shown in broken lines urges the upper and lower frames 12 and 24 away from each other. The upper frame 12 is provided with a cutting blade 22 having a cutting edge extending from the abutting surface 13 of the upper frame 12. The lower frame 24 is formed with a groove 26 for receiving the cutting blade 22 of the upper frame 12. The lower frame 24 is further formed with an insert aperture 30 which intersects the groove 26 and will support an optical fiber 31 to be cut at right angles to the cutting edge of the blade 22.
With this arrangement, after the optical fiber 31 has been inserted in the insert aperture 30, the upper frame 12 is moved to the lower frame 24 (FIG. 1c) so that the optical fiber 31 is cut by the cutting blade 22. Reference numeral 31a denotes a cut waste piece of the optical fiber 31.
With the construction of the cutter of the prior art above described, a part of the cutting edge of the cutting blade 22 to be used for cutting optical fibers is imperatively limited to a particular point on the cutting edge because the cutting blade 22 is fixed at one location on the upper frame 12.
In cutting an optical fiber for forming one end face of the optical fiber, a satisfactory end face of the fiber could not be obtained unless a cutting edge of a cutting blade is under a particularly limited condition.
In case that several cutting blades having the same shape made of a usual carbon steel are prepared by which optical fibers are cut by way of experiment, some of them are able to be used for cutting fibers more than ten times, while some of them become dull only after cutting once or twice. It is clear from this fact that cutting result is greatly affected by finely slight change in condition of cutting edge. Accordingly, a cutting edge of a cutting blade and a cut result of optical fibers are in a delicate relation.
Under such circumstances, in order to form end faces of optical fibers by the use of the technique of the prior art above described, a cutting blade must be exchanged every cutting of one fiber. This is inefficient.